Detergent foam generator

ABSTRACT

A detergent foam generator attachable to a floor cleaning appliance having at least one rotary brush and comprising a liquid reservoir casing, which may be made of plastics material, formed with a tubular portion in which is an electric motor driving a fan and having a cap forming an airflow path containing a nonreturn valve to a pipe extending into the interior of the casing, and a foam outlet pipe leading from the top of the casing out to therebelow.

United States Patent lnventor Douglas Albert Hahn Chinnor, England Appl.No. 813,662 Filed Apr. 4, 1969 Patented Feb. 16, 1971 Assignee R'eclcitt& Colman Products Limited Dansom Lane, Hull, England a British company.by mesne assignments DETERGENT FOAM GENERATOR 4 Claims, 3 Drawing Figs.

U.S. Cl. 222/190, 15/50, 261/30, 261/121 Int. Cl. A471 13/00, B67d 5/58Field ofSearch 221/251;

[56] References Cited UNITED STATES PATENTS 3,466,690 9/1969 Cooper15/50 3,467,977 9/1969 Helm 15/29 Primary Examiner-David M. BockenekAttorney-Hall, Pollock and Vande Sande ABSTRACT: A detergent foamgenerator attachable to a floor cleaning appliance having at least onerotary brush and comprising a liquid reservoir casing, which may be madeof plastics material, formed with a tubular portion in which is anelectric motor driving a fan and having a cap forming an airflow pathcontaining a nonreturn valve to a pipe extending into the interior ofthe casing, and a foam outlet pipe leading from the top of the casingout to therebelow, 7

PATENIED FEB 1 6197! 3,563,418 SHEET 1 UF 3 b 7/4 Frame Mme Am! Q vflflornaya' 1 DETERGENT FOAM GENERATOR BACKGROUND TO THE INVENTIONblowing air through the liquid detergent.

The simplest way of foaming a detergent liquid is to blow air throughit, but the application of this method to floor cleaning appliances hashitherto required complex apparatus with the air supply obtained fromthe motor of the appliance, the use of a float valve to control thelevel of the liquid detergent, and the use of nonretum valves to protectthe necessary pump and driving motor from the generated foam.

This invention relates to detergent foam generators for convertingliquid detergent into foam as cleaning material forcarpets, floors andfloor coverings and has for its object to pro vide a detergent foamgenerator unit for connection to existing floor cleaning applianceshaving at least one rotary brush for use when foam is required to beapplied to a floor.

To this end according to the present invention a detergent foamgenerator unit for attachment to a floor cleaning appliance comprises aliquid reservoir casing with an open ended tubular portion extendingtherethrough and having an inwardly extending peripheral constrictiontherein, a unit comprising an electric motor driving a fan in acylindrical housing disposed in said tubular portion with its fanhousing seated on the constriction therein, a top plate with an aperturetherein normally closed by a ball or the equivalent and locating aspring pressing on the motor unit, a cap for confining the movement ofthe ball and forming an airflow path to a pipe extending through the topof the reservoir casing to near the bottom thereof, a foam dischargepipe extending through the bottom of the. reservoir casing to near thetop thereof, and a filling aperture with closure means provided at anupper part of the reservoir casing external wall.

Preferably the casing forming the liquid reservoir is moulded inplastics material.

The constriction in the open end tubular portion of the casing may be anintegral inwardly directed flange but it is preferred to form suchconstriction by deformation of the wall forming such tubular portion.

The external wall of the reservoir casing may also be formed with anoutwardly directed flange or projecting wall deformation of uniform orvarying extent of projection to stiffen such external wall as well asprovide a convenient finger grip for transporting the unit and holdingit when attaching it to and removing it from a floor cleaning appliance.

The foam generator unit may be provided with means for attaching it tothe floor cleaner appliance or with means to be engaged by securingmeans provided on such appliance, and the shaping of the reservoircasing and in particular of the bottom thereof may be such as to adaptit to seat on the uppermost part of the floor cleaning appliance.

Current conducting leads to the electric motor extend through the topplate of the unit and are taken to a switch, either provided on the unitor mountable on the floor cleaning appliance, to switch on the electricmotor when a generation of detergent foam is desired.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the unit in elevation;FIG. 2 is a plan view looking down on FIG. I; and FIG. 3 is a sectiontaken on the line III-Ill of FIG. 2.

DESCRIPTION or PREFERRED EMBODIMENT or THE INVENTION The foam generatorunit, illustrated in the said drawings, comprises a liquid reservoircasing comprising an external wall 1 and an internal wall 2, forming anopen end tubular portion,

spaced from such external wall 1 by a top end wall 3 and a bottom endwall 4; such external wall being either circular as shown or of otherconfiguration and the tubular portion either symmetrically oreccentrically disposed relative thereto.

The wall 2 is formed with an inwardly directed peripheral constrictionas an integral flange and as illustrated as a deformation 2 of suchwall. The external wall 1 is preferably also provided with an externalflange, as a stiffener and to provide a finger grip, and as shown formedas a deformation 1 of such wall 1. The deformation 1 may projectoutwardly to a uniform extent or to a varying extent around at leastpart of the extent of such wall 1, and the lower part 1 of suchdeformation may slope substantially as shown in the drawing (FIG. 3).

An airflow pipe 5 extends through the top wall 3, where it is held as bya rubber grommet 5, to extend to near the bottom wall 4. The lower endof such pipe 5 is conveniently cut at an angle, as shown at 5, when thelonger length edge may abut the internal surface of the bottom end walld.

A foam discharge pipe 6 extends'through the bottom end wall 4, to whichit is conveniently secured by clamping nuts 7, 8 sandwiching the ambientportion of such wall between them, and extends to near the top end wall3.

An air supply unit comprising an electric motor 9 driving a fan within ahousing 10 is positioned in the tubular portion of the casing with itshousing 10 seated on. the constriction deformation 2.

A top plate 11 has an aperture 12 therein with the ambient portionthereof shaped to form a seating for a ball 13 and to locate a coilspring 14 disposed between such plate 11 and the airflow unit to keepthe latter in position with the fan casing 10 seated on the deformation2. The pipe 5 extends through another aperture in the plate 11, throughwhich plate also extends the cover outlet 15 of electric leads 16 to theelectric motor 9.

A cap 17 is disposed over the top plate 11 and attached to the top endwall 3 so also securing the plate 11 thereto, and so forms an airflowduct from the orifice 112 to the pipe 5 as well as confines thedisplacement of the ball 13, which forms a nonreturn valve, on it beingunseated by the airflow generated by the fan on operation of the motor9.

A filling orifice 18 is provided at an upper part in the external wall 1and provided with a closure cap 19 to allow detergent liquid to becharged into the reservoir up to a convenient level such as thatindicated in the drawing (FIG. 3).

The casing is preferably formed as a moulding in plastics material,conveniently in one piece by the spin moulding technique, and hasmoulded-in nuts 20 to be engaged by the securing screws 21 which fix thecap 17 and top plate 11 to the top end wall 3. t

The foam generator unit is intended to be used with a floor cleaningappliance provided with at least one rotary brush and to be placed onthe housing of the floor engaging part thereof, being provided eitherwith means for attaching it thereto or with means engageable byattachment means provided on the appliance.

When required to generate foam from detergent liquid charged into thereservoir, the motor 9 is switched on to drive the fan in the casing 10which draws air upwardly through the tubular portion of the casing andunseats the ball 13 for the airflow to pass down through the pipe 5 andout into the liquid to bubble up therethrough with the formation of foamabove the liquid level which is carried down through the pipe 6 to falltherefrom onto the floor to be cleaned by the cleaning appliance towhich the generator unit is fitted.

lclaim:

l. A detergent foam generator including a liquid reservoir comprising acasing having an external wall and a tubular internal wall spaced fromsaid external wall by top and bottom end walls, an inwardly directedperipheral constriction in said tubular internal wall, an airflow unitcomprising an electric motor and a driven fan in a cylindrical housingseated on said peripheral constriction, a top plate with an aperturetherein,

means for attaching said top plate to said top end wall, spring meansbetween said top plate and said airflow unit, a displaceable ball toclose said aperture in said plate, a pipe extending through said topplate and said top end wall to near said bottom end wall, cover means,means to connect said cover means to said top plate to confinedisplacement of said ball and to form an airflow path to said pipe, adischarge pipe extending through said bottom end wall to near said topend wall, and a closable filling orifice in said external wall.

2. A detergent foam generator as claimed in claim 1, in

which said liquid reservoir casing is a moulding in plastics material.

3. A detergent foam generator as claimed in claim 2, in which saidperipheral constriction is formed by deformation of said tubularinternal wall.

4. A detergent foam generator as claimed in claim 2, in which saidexternal wall is deformed to provide an outwardly projecting rib.

2. A detergent foam generator as claimed in claim 1, in which saidliquid reservoir casing is a moulding in plastics material.
 3. Adetergent foam generator as claimed in claim 2, in which said peripheralconstriction is formed by deformation of said tubular internal wall. 4.A detergent foam generator as claimed in claim 2, in which said externalwall is deformed to provide an outwardly projecting rib.